Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!uflorida!novavax!hcx1!hcx2!jgj
From: jgj@hcx2.SSD.HARRIS.COM
Newsgroups: comp.sys.atari.st
Subject: Re: Blitter problem
Message-ID: <46700013@hcx2>
Date: 6 Oct 88 17:43:00 GMT
References: <39610@yale-celray.yale.UUCP>
Lines: 20
Nf-ID: #R:yale-celray.yale.UUCP:39610:hcx2:46700013:000:1157
Nf-From: hcx2.SSD.HARRIS.COM!jgj    Oct  6 13:43:00 1988


> With the blitter turned off, everything is fine.  With it on, partial
>"shadows" of the window border get left behind when I drag a window
>across the screen with the mouse.  These are little vertical lines of

By any chance, are you running one of those clock accessories that put the
time in the upper right hand corner?  I observed the same thing, but only
when that clock accessory is installed.  I suspect it involves a reentrency
problem with the routines.  The accessory performs (I assume) a-line operations
from interupt level and the code that handles the hardware blitter gets 
confused when it gets to many pending requests.  Atari, can you say 
"semaphore"?  Realize that this is a guess.  Since the fastest speed up
I have ever clocked the  blitter to have was about 5%,  Just turn the blitter
off and forget it was ever there.

============================================================================
Jeffrey Glen Jackson  | Satan jeered, "You're dead meat Jesus, I'm gonna
jgj@ssd.harris.com    |     bust you up tonight."
                      | Jesus said, "Go ahead, make my day."
                      | -- Carman, "The Champion"